Answer: -600 and 1600 were invested into the two accounts.
Step-by-step explanation:
x = amount invested in the first account.
y = amount invested in the second account.
You start off with this equation
Subtract both sides by y.
Subsitude 1000 - x for x for the second equation.
Use the distributive property to solve for y.
Subsitude -600 for y in the first equation and solve for x.
-600 and 1600 were invested into the two accounts.